A survey of certain neuropterous predators and the relative abundance of the important neuropterous predatory insects were studied  by using a light trap during two successive years at Mansoura district. The obtained results recorded four neuropteruos predators trapped during the two years of study. These species belonging to two families : Chrysopidae and Myrmeleonidae. These predators were namely: Chrysoperla carnea (Steph.) ; Chrysopa septempunctata Wesm.; Cueta variegata Klug. and Palpares cephalotes Klug. The dominant species was C. carnea during the two years of investigation. The data showed that C. carnea had six peaks in the first year and five peaks in the second year of study. These peaks were recorded in the fourth week of March; fourth week of April; first week of June; third week of July; third week of August and second week of October; while in the second year these peaks were recorded in the first week of April; first week of June , first week of July, first week of August and fourth week of September, respectively. The obtained data revealed that C. septempunctata had four peaks in the first years and three peaks in the second years. These peaks were recorded in the first week of June, third week of July, fourth week of August and second week of October, respectively in the first year, Meanwhile, these peaks were found in the second year of study, in the first week June, first week of July and fourth week of August. The statistical analysis assured that, there was a highly positive significant correlations between the biweekly catch of C. carnea and C. septempunctata and temperature parameters during the two years of study. While, the relative humidity parameters had insignificant effect on the population density of the two predators during the two years of investigations.